1. Field of the Invention
The invention relates to a lighting source structure, and in particular, to a lighting source structure that replaces the filament of a conventional light bulb with a lighting object that produces light.
2. Description of the Prior Art
Light bulbs are an indispensable part of our daily lives. FIG. 1 illustrates a conventional bulb 1 that uses a filament 5 for generating light. The filament 5 is connected to a first electrode 2 and a second electrode 3. The first electrode 2 and the second electrode 3 are connected to a base 4 and to an electrical power source. When conducted, the electrical power source will supply electricity to the filament 5 to cause it to generate light and heat. Since the conventional bulb 1 has many disadvantages (e.g., large consumption of energy and short life), light emitting diodes (LED) have gradually begun to replace conventional bulbs as light sources.
FIG. 2A illustrates a conventional LED lighting structure having an LED 11 that is positioned in the center of a metal reflector cup 12. An encapsulation tube 16, which is made of epoxy resin or its compounds, encapsulates the LED 11 and the metal reflector cup 12. The metal reflector cup 12 is connected to a first electrode 13. The LED 11 is connected to a metal conductive thin thread 15 that is connected to a second electrode 14. The first electrode 13 and the second electrode 14 are connected to a power source (not shown) which provides electricity to enable the LED 11 produce a light beam that projects from the hemispherical front end of the cup 12 to form a lighted area 18. The top surface 17 of the encapsulation tube 16 has a hemispherical configuration to function as a convex. The position of the LED 11 in FIG. 2A is the focus point 19 that is formed by the top surface 17 of the encapsulation tube 16 functioning as a convex, so that the light in the lighted area 18 will focus and be reflected to produce a light beam projecting out from the LED lighting structure.
LEDs provide numerous benefits when compared with incandescent and fluorescent illuminating devices, including lower power requirements, high efficiency and long life:
1. Low power requirement: Most types of LEDs can be operated with battery power supplies.
2. High efficiency: Most of the power supplied to an LED is converted into radiation in the desired form, with minimal heat production.
3. Long life: When properly installed, an LED can function for decades.
However, the lighting structure in FIG. 2A still suffers from some drawbacks since the configuration and structure of the reflector cup 12 and the encapsulation tube 16 tend to decrease the intensity and scope of the light that is projected from the LED 11. For example, as seen in FIG. 2A, the lighted area 18 is narrow. If the LED 11 can be moved closer to the top surface 17 while maintaining the same location for the focus point 19 (i.e., so that the LED 11 is now positioned between the focus point 19 and the top surface 17), as shown in FIG. 2B, the lighted area 18 will cover a wider area. However, the conventional LED bulbs that are available in the market cannot provide such improved lighting effects, thereby rendering such bulbs inappropriate for many applications.